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DaveKamp 
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 Posted: 18 Oct 2010 at 7:45am |
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The crank might not be bent, but at the time the rod beam deflected, there was probably quite a bit of deflection... the crank is somewhat of a rubber band when loaded like that.
Hydraulic locking isn't limited to coolant- since you're running methanol, a substantial amount of your incoming fuel comes in as droplets... and will tend to fall to the bottom of the chamber, and what doesn't burn (because the flame speed of methanol is slower than that of hydrocarbon fuels) you'll get a fair amount of unburned fuel pitched out the stack on full-roar. While passing TDC, the liquid component of fuel will be in that squish-band, driving your CR WAY up, and if there's enough fuel in there at the time, the amount of compressable (gasses) volume may not be quite enough to let that piston reach TDC.
Diesels with leaky injectors can wind up in the same situation.
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mlpankey
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Posted: 18 Oct 2010 at 8:40am |
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Dave ,are you certain on the flame speed ?
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Gerald J.
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Posted: 18 Oct 2010 at 10:57am |
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Its possible the rods that were tight but don't appear bent are bent near the ends. That the rod bowed like ) but didn't reach yield in the middle of the bow, just at the ends by the journals and bent those. Its time to inspect those rods with flat plate, and pins to find the ends by the shop manuals for parallel journals and twist of rod. Usually done with a surface plate, those two pins and some precision measuring apparatus. Twist requires a matched pair of v blocks.
I'm suspecting that Buda did the same thing to rods working out how heavy they should be, then made them heavier until their test engines didn't bend any in normal use. Then they added metal to just keep them from bending at normal power.
You need tougher rods.
Gerald J.
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Brian Jasper co. Ia
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Posted: 18 Oct 2010 at 11:44am |
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Just curious here, if crank deflection is a problem, has Mitch reached the max power capability of the envelope? All this engineering talk is interesting. Anybody making super strong 226 cranks?
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"Any man who thinks he can be happy and prosperous by letting the government take care of him better take a closer look at the American Indian." Henry Ford
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mlpankey
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Posted: 18 Oct 2010 at 12:16pm |
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I agree Gerald I need stronger rods. Now my question is with a 780 gram piston how light should the rod be and have a high tensile yield . Still trying to stay in the law of coservation of energy being absorbed and transferred to the fly wheel as torque . Rather than being drove through the crank creating flex and other detrimental characteristics. You are also probably right on how Allis engineers determined if rods would endure . My hip pocket cant continue to endure . Hip pocket needs to feal the cost of what ever rod material and production cost it takes to endure only once.
Edited by mlpankey - 18 Oct 2010 at 12:37pm
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Gerald J.
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Posted: 18 Oct 2010 at 2:28pm |
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No matter how sturdy, all the drive parts, from the piston, the block, the rods, and the crankshaft have flex and springiness. Besides conservation of energy, the heavier the piston and the rod, the more weight to be balanced and if its a typical 4 cylinder tractor crankshaft without balance weights you don't have that balance, so you have inertia effects that are unavoidable and get worse with heavier parts. Without applying slide rule to formulae that I don't know involving column buckling and forces on the rod in the engine, my next rod would have half again the height and thickness to increase bending strengths by a factor of 3 compromising with thinner sections to cut the bending strengths in both planes back to about twice the Buda rods. Then I'd want to go to better steel, presuming the Buda rods are more ordinary than 4340, but I don't know that to be sure. They could have used great steel so changing the steel won't help.
There should be experts in hot rodding rods that know how best to minimize bent rods and broken blocks while not impacting inertia and balance too much.
Gerald J.
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Gary in da UP
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Posted: 18 Oct 2010 at 4:06pm |
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Clutch is slippen' can't get traction, my guvn'r weights blew up, my connectin' rods are pretzl shaped. But I got compression, and a little bitty distributer that'll power 40 miles of bob wire fence. Why bother? Do you keep hitten yourself in the head with a hammer cuz' it feels so good when you stop? You seem to have some deep pockets thanks to your union job, or maybe you have some gubment grant money so you can explore the beaking point of innocent AC tractors and you provide some amusement, so to each his own. But you have never answered my ? Are you havin' fun?
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mlpankey
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Posted: 18 Oct 2010 at 4:34pm |
Any true blooded hotroder knows the answere .yes its fun . Its not as much monkey see monkey do as drag racing or dirt track. Yes making the ponies to tax the snott out of parts is cool. See the deal with the traction is the 15.5 /38 couldnt hold the power for three gears and the clutch couldnt hold the power for road gear and that was even with the rods shortening. So why do top fuel crews rebuild after every run so they can boast about having 8000 hp and driving through clutches right into 300 mile an hour. just hearing one of them makes me giddy . Spectators who were around the tractor friday night before the parts failed were giddy as well for you couldnt hardly move to the line for people comming up to it to feal the ground jar.
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mlpankey
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Posted: 18 Oct 2010 at 4:41pm |
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[QUOTE=Gerald J.]No matter how sturdy, all the drive parts, from the piston, the block, the rods, and the crankshaft have flex and springiness. Besides conservation of energy, the heavier the piston and the rod, the more weight to be balanced and if its a typical 4 cylinder tractor crankshaft without balance weights you don't have that balance, so you have inertia effects that are unavoidable and get worse with heavier parts. Without applying slide rule to formulae that I don't know involving column buckling and forces on the rod in the engine, my next rod would have half again the height and thickness to increase bending strengths by a factor of 3 compromising with thinner sections to cut the bending strengths in both planes back to about twice the Buda rods. Then I'd want to go to better steel, presuming the Buda rods are more ordinary than 4340, but I don't know that to be sure. They could have used great steel so changing the steel won't help.
There should be experts in hot rodding rods that know how best to minimize bent rods and broken blocks while not impacting inertia and balance too much. Gerald
We balanced the entire rotating assembly externally . You may be surprised then again you may not be surprised as to how bad a 226 stock engine is out of balance. ever notice how the hand clutch vibrates on them
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Gerald J.
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Posted: 18 Oct 2010 at 6:31pm |
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Most slow speed 4 cylinder engines have no balance weights and so are out of balance all the time. Balancing externally takes care of the external world but works the crank shaft even harder. When you find the next step in sturdier rods, you will have to do that external balancing all over.
Gerald J.
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mlpankey
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Posted: 18 Oct 2010 at 7:14pm |
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yes every time you change a gram . even though it can be argued that in a in-line engine with piston motion strait up and down the two cylinders 1 and 4 and 2 and3 cancel each other.
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Gerald J.
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Posted: 18 Oct 2010 at 7:51pm |
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Except you still have that couple between the two cylinders going in opposite directions.
And you wish that the couple from the front pair is opposed by the couple from the rear pair, but for higher speed, like my VW 2 L engine runs a fully balanced crankshaft for each cylinder runs smoothly up to at least 7000 rpm.
Gerald J.
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mlpankey
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Posted: 18 Oct 2010 at 7:56pm |
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we are on the same page. even though the automotive crank balancer that's in the machine shop i have the door key to just spins them a tic over 5g. PS crutch came through with the formula over on yts pulling forum . I had a few hecklers like Garry over there also.
Edited by mlpankey - 18 Oct 2010 at 8:02pm
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Gerald J.
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Posted: 18 Oct 2010 at 9:11pm |
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A good sensitive balancer doesn't need speed, look at the modern tire balancing machines that balance a tire at less than 200 rpm. And you can't ever do a perfect balance job on a crank shaft because you have easily balanced parts like the crank journal and webs and the big end of the connection rod spinning in a circle coupled to the rod and the piston that don't spin in the circle but start and stop going in a linear path and the shank of the rod gets split between reciprocating and spinning parts.
Then to add confusion to the coupling between the recipricating parts and the crank, the center of the crankshaft can be offset from the center of the cylinders to cut down on piston slap, to make the angle of the connecting rod less on the power stroke than the compression stroke. On top of that there's different forces on the piston each of the four strokes, probably smallest on intake (actually pulling against the piston, lifing the rod off the journal, riding on the rod cap), bigger on exhaust, a fair amount bigger on the compression stroke and then relatively huge on the power stroke.
Gerald J.
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mlpankey
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Posted: 18 Oct 2010 at 9:25pm |
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tire balancing machines. I remember working at the local full service gas station as a kid advancing up from pumping gas to tires then brakes to ac . I remember be excited at the purchase of the spin tire balancer . It would balance a tire at a rpm that would equate to 60 mile an hour when driving . gave you the weights needed on each side of the wheel in a digital read out . Its long gone and I still think the bubble balancer it replaced did as well if not better. oh well lets crunch some numbers . enjoyed it.
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Ken(MI)
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Posted: 19 Oct 2010 at 8:22am |
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If you're going to push the envelope Mitch, you are going to break things doing it, plain and simple, engineering goes a long way, but engineering, coupled with testing goes further. Jet Engineering pioneered Titanium rods, rocker arms, valves, retainers and other race components almost thirty years ago, I was there, and made a lot of stuff that never even survived one dyno session. Hang in there, but if you don't want things to break, stay with the tried and true. By the way, 4340 is not considered chrome-moly steel, that title is reserved for the more garden variety 4130/4140 series that are easily weldable. 4340 get's the Boy-Dog status from the addition of 2% nickel, which is why it is designated a Cr-Ni-Mo steel, and has poor weldability amongst other significant differences, including the requirement of avoiding certain temperature ranges during heat treatmetn and tempering. You told me those Buda rods were forged at Atlas, which has me betting that they are nothing more that 1035 SBQ, if so, going to 4340 will give you two to three times the strength with proper heat treatment. Good luck
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Hudsonator
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Posted: 19 Oct 2010 at 6:43pm |
Here's a hint:
Give up some of that compression height on your piston pin location and get a rod that can offer you something beyond a 1.27 rod ratio. I'd have never wasted all that area and run a rod with anything less than a 1.57 ratio.
By the time you spend a ton of money on a rod beam that can stand such an angle, you'll be pushing pistons through your block sideways.
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There isn't much a WC can't do.
WD's just do it better.
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mlpankey
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Posted: 19 Oct 2010 at 8:02pm |
Hudsonater I am sticking with the short rod. Talked with Carrillo today . I know your a fan of long rods but increased stoke keeps rod ratios low sleeves cannot be long enough to keep ring flutter and piston stability to utilize a short skirt. We already know that a short rod moves away from tdc sooner . We already know what advancing a cam does for torque and horsepower as well as it open and closes the intake valve sooner so with the longer dwell at bdc we can have 2 to four more degrees of duration which in Siamese intake keeps reversion from happening . We also know that the mountain motors that do battle on the 1/4 mile at 800 plus cubes at 8000 rpms run a 1.3 rod ratio . We all ready know that long strokes like a cam with wide lobe centers . So tell me what I don't know after all we are not building a Indy car motor nor are we building a 9200rpm cup motor. Heres a article written by mine and Larrys came grinder.
Also do some asking around I think you will be surprised by who and how many 226 tractor pullers/ builders use that buda rod. To clarify WE its me and you.
Edited by mlpankey - 19 Oct 2010 at 8:19pm
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DaveKamp
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Posted: 19 Oct 2010 at 10:33pm |
In free atmosphere, and at stoichiometry, methanol combustion occurs at a higher flame speed than gasoline, however, when you're feeding an engine large volumes of methanol, a substantial chunk of that incoming fuel is NOT atomized, so you don't have stoich... you have 'wet' fuel. If you put an observation camera inside the chamber, and measure flame speed under running conditions, you'll see that under said conditions, the effective flame speed is SLOWER, simply because the 'wet' fuel slows the flame front down. One of the advantages, is that methanol, burning in the chamber with a 'wet fuel' state, can be started early, and will maintain a burn as long as the fuel continues to heat and atomize. In this case, a long-rod engine will make better use of methanol's extended burn time, you'll lose less energy to high rod-angle piston scuff, and won't be rubber-banding the crank as much, so I'd be inclined to go with Hudson's suggestion. Added bonus to the long rod, is that the G-forces subjected to the upper half of the reciprocating assembly are dramatically reduced. If you're intent on spinning it fast, that's a prime way to keep it from coming unglued. If you look at the data shown in the table below, you'll see that the vapor pressures, heat of vaporization, and net heating values are substantially different... so methanol is a totally different planet. And on another side note- notice the ignition energy required... methanol requires LESS (at stoich) than gasoline... Methanol Ethanol Unleaded Gasoline
RON 106 107 92 - 98
MON 92 89 80 - 90
Heat of Vaporization (MJ/kg) 1.154 0.913 0.3044
Net Heating Value (MJ/kg) 19.95 26.68 42 - 44
Vapour Pressure @ 38C (kPa) 31.9 16.0 48 - 108
Flame Temperature ( C ) 1870 1920 2030
Stoich. Flame Speed. ( m/s ) 0.43 - 0.34
Minimum Ignition Energy ( mJ ) 0.14 - 0.29
Lower Flammable Limit ( vol% ) 6.7 3.3 1.3
Upper Flammable Limit ( vol% ) 36.0 19.0 7.1
Autoignition Temperature ( C ) 460 360 260 - 460
Flash Point ( C ) 11 13 -43 - -39
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mlpankey
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Posted: 20 Oct 2010 at 6:44am |
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Piston skirt scuff from side loading . Heres a fact .been running since 2000 either a international rod 7.25 long or the buda rod 7.375 long on the same arias 4 1/8 bore forged piston with same piston pin location and skirt length. Creates a 11.1 cr on the 7.25 rod and a 14.1 on the buda rod with a 4 1/8 bore. I currently sold these pistons to another individual this year but they had no skirt scuffs at all nor had the ring lands opened up any. Also we run a closer plug gap with methanol a msd 7al 2 box the six doenst have enough energy and we run less total timing . Due to the faster flame speed than a race gas of the same Ron/Mon rating for a compresssion ratio of 15.3 to 16.1 . The article above compared apples to oranges .Since you run twice as much methanol as gasoline you have a cylinder cooling affect but you also loose intake runner space for incoming air so you have to utilize the extra duration on a cam shaft and create as much depression under the intake valve as you can . Its kinda like Grumpy Jenkins said . When the engine runs better than your thoughts you need to change your thought process and not the engine. I just need to find a little more longivity in superior products rod material and not back the power down to have longivity from a inferior material.
Edited by mlpankey - 20 Oct 2010 at 6:56am
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Bob D. (La)
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Posted: 20 Oct 2010 at 7:39am |
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Panky, Not knowing even 5% of what you know about these mods, my question is this: When you get a rod that holds up to these parameters, what is going to break next. Of course, it will be either nothing or the next weakest link. How much damage might that cause?
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When you find yourself in a hole,PUT DOWN THE SHOVEL!!!
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mlpankey
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Posted: 20 Oct 2010 at 7:41am |
Not all methanols are created equal as well.
Methanol Fuels for Racing
Tech Bulletin
VP offers several types of methanol racing fuels, each of which offers top quality for applications ranging from drag racing, circle track and road racing to off road and powerboats. Among the most important features of VP’s methanol products is consistency in production and pack- aging. Much of the cheaper methanol on the market is reclaimed from industrial processes and far more likely to contain contaminants. VP doesn’t cut corners or ‘reclaim’ methanol. While that leads to slightly higher prices, our customers can trust our product and have much greater assurance they won’t have to deal with “bad fuel” issues.
Why offer three types of methanol?
VP has always emphasized giving our customers options. We try to make sure we always have the absolute best performing option available, making the most power possible given an application’s parameters. But there are other considerations—budget, fuel rules, or environment for example—that sometimes dictate the selection of a fuel other than one that makes the most power.
M1TM - M1 is the best straight methanol on the market. No frills, but consistently 99.85+% pure and always packaged in lined drums, as are all VP fuels. That means no contaminants and peace of mind from knowing you don’t have to deal with fuel issues. When fuel rules require the use of straight methanol with no additives, M1 is the best option.
M3TM - M3 contains combustion and lubrication additives that improve vaporization and increase burning speed. These factors, combined with a better seal of the rings due to the lubrication additive, make substantially more power than straight methanol—up to a 50 Hp gain in a 1030 Hp engine. The improvement in throttle response is also significant—up to a 5% increase in torque across a wider rpm range. On-track results indicate a .02-.03 improvement in ET in the 1/8 mile. The improved combustion also helps the thermal efficiency of the air/fuel mixture. This expands the range of ignition, contributes to better ‘startability’ and more consistency run to run, while lowering the exhaust temperature 40-100°. Not only will M3’s improved combustion make more power and offer better protection against detonation, it also inhibits the noxious fumes you typically get with standard methanol, so it’s much easier on your eyes and nose. A somewhat unexpected benefit of M3 is a 30% decrease in fuel consumption. That means if you typically use 40 gallons over a race weekend, you’ll only need about 25-30 gallons of M3. M3 also includes an anticorrosion package, so there’s no need to add anything else to address lubrication or corrosion issues.
To maintain the original properties and comply with Health and
Safety regulations, this fuel should be handled and stored in a cool
place and always maintained in tightly sealed drums.
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Property/
Typical Values |
M1 |
M3 |
M5 |
Test
Methods |
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Specific Gravity
@ 60F° |
.795 |
.784 |
.816 |
ASTM D 4052 |
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Reid Vapor
Pressure |
4.60 |
8.57 |
7.66 |
ASTM D 323 |
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Color |
Clear |
Clear |
Clear |
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Since M3 is not make more power than M3, while offering the same or better protection against detonation. Like M3, M5 offers a wider range for tuning, as reflected by the fact that the bracket racers who have helped us in testing have experienced no problems with tuning or tuning consistency. M5 also reduces noxious methanol fumes, although not as well as M3. That means that while M5 is the best choice for making the most power in unrestricted applications, M3 will still be the best option for some venues, notably enclosed stadiums. M5 is not pure methanol and won’t pass a water test.
M2TM Upper Lube – Designed for use in methanol-powered engines, M2 protects valves, guides, cylinder walls, fuel pumps and aluminum fuel systems, and extends pump life. Using electrochemical plating technology—a big improvement over just using oil—M2 leaves a thin film of lubrication to protect against corrosion between races. Recommended for use with M1 or any other standard methanol, while it’s not required with M3 or M5 due to their lubrication additives.
Technical questions on applications and tuning can be referred to VP’s Technical Department at 812-878-2026 or tech@vpracingfuels.com. VP’s methanol products can be ordered via any of VP’s regional distribution centers, contact information for which is available on VP’s website at vpracingfuels.com. VP’s methanol products are available in 5-gallon pails and 54-gallon drums, as well as bulk.
The four most important properties of racing fuel
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mlpankey
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Posted: 20 Oct 2010 at 7:45am |
 Bob D. (La) wrote:
Panky, Not knowing even 5% of what you know about these mods, my question is this: When you get a rod that holds up to these parameters, what is going to break next. Of course, it will be either nothing or the next weakest link. How much damage might that cause? |
Thats always a concern. what breaks next .Probably gears.
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Amos
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Posted: 20 Oct 2010 at 7:53am |
I have had my bad experiences with weak parts when I was much younger. You have a vast knowledge, everyone who has replied to this thread,and I have been absorbing the information I have read here. Only thing I really want to do is see your tractor run, as I am pretty confident that it will run real well, when it is repaired of course.
One thing I can tell you about titanium rods is they will break if you get things out their proper settings, especially ignition timing problems. That was a very expensive lesson I learned. They were a lot cheaper back when I bought them as compared to the price I saw you post earlier.
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Butch(OH)
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Posted: 20 Oct 2010 at 9:20am |
mlpankey wrote:
Hudsonater I am sticking with the short rod. Talked with Carrillo today . I know your a fan of long rods but increased stoke keeps rod ratios low sleeves cannot be long enough to keep ring flutter and piston stability to utilize a short skirt. We already know that a short rod moves away from tdc sooner . We already know what advancing a cam does for torque and horsepower as well as it open and closes the intake valve sooner so with the longer dwell at bdc we can have 2 to four more degrees of duration which in Siamese intake keeps reversion from happening . We also know that the mountain motors that do battle on the 1/4 mile at 800 plus cubes at 8000 rpms run a 1.3 rod ratio . We all ready know that long strokes like a cam with wide lobe centers . So tell me what I don't know after all we are not building a Indy car motor nor are we building a 9200rpm cup motor. Heres a article written by mine and Larrys came grinder.
Also do some asking around I think you will be surprised by who and how many 226 tractor pullers/ builders use that buda rod. To clarify WE its me and you. |
I'm glad you posted that link Mitch because waaay back when I first started playing with big Chevy motors screwing around with the rod lengths became the darling of everyone looking for magic HP increases and every magazine publisher was soon touting long rods as like adding nitro to the fuel tank. Soon every maker was working 7 days a week building rods of magic proportions for any need or speed. Being basicaly a "show me" kind of guy I set up a test stand with my big degree wheel and could measure piston travel vs degrees of crank rotation and came to one conclusion about magic happening when messing with the rods,,,B** S*** Anyone with a 2nd grade education could see there would be changes in side loadings that would be benifical but if the drag was what some say it is the pistons would last about 2 minutes and be junk. Other than that the effect upon the piston location vs roation of the crank was GREATLY exxagerated. Since my thoughts were not main stream I kept them mostly to myself. One day I was reading a Carcraft rag and they had an article about Rehner & Morrison who back then were the guys to beat in Pro stock and Buddy Morrison actualy opened up one of their huge match race motors. Why! Exclaimed the writer, that motor shouldn't even run with thosoe short rods and the resulting rod ratio, How can this be!! Buddy responded, (not a quote but similar to) the rod hooks the piston to the crank,thats all they do. What Buddy was saying was that too comprimise other important things, like displacement, or compression ratio or cam timing in order to obtain some given rod ratio was nothing less than stupid,,,, and I agree.
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mlpankey
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Posted: 20 Oct 2010 at 9:40am |
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To add to the Rehr Morrison article Darrin Morgan who was their cylinder head guru thats now with pro filer. Said that the deck height was 8.090 which was shorter than a sbc and that was the single speed secret It simply straighten the intake runner on v8 engines which made for shorter pushrods which eliminated valve train flex issues and shorten connecting rods. Big block chevy production blocks deck heights are passenger 9.800 truck 10.200. Thats what I remember from the article they have a book on producing power thats published it even calls bs to the bs myths. Then they will be those who allude you that power producing techniques for automobile internal combustion engines dont apply to a tractors internal engine. The mechanical engineering and physic formulas are for a internal combustion engine. No disclaimer on application. PS you big block ford fans Jon Kaase when asked about rod ratios and piston speed said , I dont bother looking at it If I did everyone of them going out the door would frighten me.
Edited by mlpankey - 20 Oct 2010 at 9:50am
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mlpankey
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Posted: 20 Oct 2010 at 10:10am |
Here is another good article for gear heads like me to enjoy.
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Larry(OH)
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Posted: 20 Oct 2010 at 10:43am |
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So Butch, the old "A" have short rods in it then???
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'40 WC puller,'50 WD puller,'50 M puller '65 770 Ollie
*ALLIS EXPRESS contact*
I can explain it to you, BUT I cannot understand it for you!!
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mlpankey
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Posted: 20 Oct 2010 at 11:10am |
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to yield a 1.5 rod ratio on a 6 inch crank means the rod would be 9 inches long take 1/2 the stroke which is 3+9=12 inches . The blocks deck height is 12.656 so now you have to have ..440 thousandths including the head gasket for a compression ratio of 15.3 .1 so you have a piston of a compression height of .258
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Butch(OH)
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Posted: 20 Oct 2010 at 11:22am |
Larry(OH) wrote:
So Butch, the old "A" have short rods in it then??? |
ya there only a couple foot long, lol
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